Compound centrifugal pump.



PATBNTED FEB. |25, 51903.

E. W. RIGGS. i l GOMPOUND GENTRIFUGAL PUMP.

" APBLIOATION FILED MAY 91 1907.

lz SHEETS-SHEET z.

nnrrnn srn'rns rAranci ornrcn ERLAND W. RIGGS, OF BTTE, MONTANA., ASSIGN'OR'OF ONE-HALF TOV MORRIS' S. LARGEY, OF BUTTE,MONTAN'A.

COMP-QUND CENTRIFUGAL PUMP.

No. sedes?.

Specicaton of Letters Patent.

Patented Fen. 25, 1908.

applicativa mamy-9.. 19o?. sein Nt. 372.700.

To all whom it may concern:

Be it known that I, 'IERLAND Rrces, a

citizen of the United States, residing .in Butte, in the county, of Silverbowl and State of Montana, have invented certain-new and useful Improvements in Com ound Centrifugal Pumps and I do here y declare the following to be a full, clear,y and exact description of the invention, such as will enable others skilled in the'art to which it appertains to make and use thesame.v

My invention relates to improvements 1n compound centrifugal pumps, and the object of my invention is to provide a slmple and l5 economical dev-ice of this kind, whiclwith a small expenditure of power Will lift a large amount of water Ito a considerable height, this application being an improvement upon my former invention, Serial No. 268,598,

l'iled July 7, 1905.

is a 'longitudinal' crosssection of my invention, some of the supports not -.being shown. Fig. 2 is a vertical central cross section of the same. VF ig. 3 is a cross section of the inner fixed dilusion ring, and F ig. 4 is a vertical cross section of thel same.l

In practice the entire pump is supported upon a heavy metal frame by being securely bolted thereto,` but this frame is not shown in thel drawings7 :5 l represents 'one of the supportsfor the pump, which is securely fastened to the frame.` Through this support inv a stufling Abox 2 runs a'hollow pipe 3, the inner end of whi'ch is screwed into one side of a revoluble 0 wheel 4 provided with curved vanes 5. These vanes are contained between disks 6, each of which is perforated at the center' to .receive one end'of the pipes 3 and 7. A pulley'Sis attached to the p ipe 3 for revolving the same, 5 and this pulley is revolved by any suitable means. Y

Just outside'the revoluble wheel 4 is a fixed diffusion ring 9, which is provided with slots 10 to permit the outward 'passa e of the liquid. .This diliusion ring is held'l y means of bolts 11 between the edges. of two circular dished plates 12 and 13.. The plate 13 i's supported on the end of a tube-14, which is screwed into it, and theother end of this 5 tube is screwed into the support 1. Similarly the other plate 12 issupported on aV tube 1'5.. A' packing such as 16,. surrounds the inlet tube 3 to prevent the fluid from leaking around the edge of the wall 4. This diffusion ring 'is provided with, inclined vanes 19, 60

which are inclined in the opposite direction to that-of the blades 5. on the wheel 4.

vOutside the diffusion ring 9 is located a revolubly mounted annular wheel 17 pro,-

vi'dedwith vanes 18 curved inl the same 65 direction, as; the vanes 5. Thisl wheelis cast in one piece', and is held by means of botte 20- in the outer edges of' dished plates 21 and 22.

These plates are each provided with a central "perforatiomvand a pi e 23is screwed into the 70 central part of the p ate 21, and a pi e 24 is screwed into the centrall art of the s ate 22. Surrounding the whee s and the iiiusion ring is a stationarycasing 25 so arranged as to form a volute arrangement around the central tubesj3and 7, and terminating in a' discharge nozzle 26, and having a lattened base 27, which rests u on the supporting frame. This casino 25 1s made in two sections each providedJ with rojecting lips 28, and the sections yare unite together by bolts 29 in the usual way. This casing is also pro' vided with a series of vanes 30 just outside the valles 18 of the wheel 17, and inclined in the opposite direction from that of the vanes 35 l 18, but substantiall in the same direction as the plates 19 o n tV ediusion rino 9.l

30 represents a pulley fastened to the pipe 23, and through which the` ipe's supporting ythe inner wheel and the dni) Stuing boxes are .provided wherever the hollow' pipes pass through thev casing, or through supports, orthro'ugh each other.

I have found it preferable in practice that usion ring pass.

.the Wheels 4 and v17 should be revolved at 95 different` rates of angular-s eed, the outer one at a higher angularspee `than the'inner one.

In'the drawing I have shown two revolvjing pumps and two stationary 'diffusion 100 rings, but I do not limit myself ,tothis numbera'as three, or-even more, of each -could be use Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In a com ound centrifugal pump, the

combination o a central centrifugal pump provided with curved vanes and mounted on 'a hollow shaft, another centrifugal pump 1,10

surrounding said rstn'amed `pump and mountedmon hollowv shafts,` a stationary diffusion ring between said pumps, and means for driving the outer pump at a greater angular speed than the inner pump, substan` tially as described.

2. In a compound centrifugal pump, the. combination of a central pum a hollow shaft and provide'dp with curved vanes, an annular centrifugal pum surrounding said irst-namedpump and aving vanes curved in the same vdirection as the vanes of said first-named pump, a stationary diffusion ring provided Wlth vanes curved in4 the opposite irection to the' vanes on the pun1ps,n1eans for driving said outer pump at a greater angular s eedthan said inner pump, a` volute shape .casing surroundlng' said pumps, and inlet andv discharge pipes, substantially as described.

3. In a com ound centrifugal pump, the combination-o a central pump mounted o 'n mounted on a hollow shaft and provided With curve .I vanes, a stationary diffusion ring surroundingsa'id pump and lprovided with venes 25 curved in the oppositejdirection, a second annular centrifugal'pump surrounding said diusionring mounted on aA hollow shaft and provided With curved vanes, Athe vanes on said second pump being curved in substan- 30 ltially the same direction as those on the 

